Machine for cutting gear teeth



Dec. 4, 1928. W. E. SYKES MACHINE FOR CUTTING GEAR TEETH Filed Dec. 28, 1925 10 Sheets-Sheet l M w 5 m 1 6 I a I 6 M l 7 I n 4 6 MF L B I 4 l v l I" w 0 5 W l mm o a ll wb 2 2 O o a o i m I M 4 mu Dec. 4, 1928.

W. E. SYKES MACHINE FOR CUTTING GEAR TEETH Filed Dec. 28, 1925 10 Sheets-Sheet 2 6410: neg

Dec. 4, 1928.

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W. E. SYKES MACHINE FOR CUTTING GEAR TEETH Filed Dec. 28, 1925 10 Sheets-Sheet' Dec. 4, 1928.

1,694,042 w. E. SYKES MACHINE FOR CUTTING GEAR TEETH Filed Dec. 28, 1925 10 Sheets-Sheet 5 Jmlllmh 'lw m 145 H Dec. 4, 1928.

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- w. E. SYKES MACHINE FOR CUTTING GEAR TEETH Filed Dec. '28 1923 10 Sheets-Sheet 8 :IMH IIi Dec. 4, 1928.

w. E. SYKES MACHINE FOR CUTTING GEAR TEETH 10 Sheets-Sheet 9 I g'mn'nfo'o fluom Filed Dec 28", 1923 Dec. 4, 1928. 1,694,042 w. E. SYKES MACHINE FOR CUTTING GEAR TEETH Filed Dec. 28, 1923 10 Sheets-Sheet l0 2.07 I77 I q l E 3 W L fl :2- 0 21s 23) I f: Z::::: v 230 223 22/ n I H 170 I ISO 0 0 I68 QT I: 0 0 I49 Patented Dec. 4, 1928.

UNITED STATES W ILLIAM EDWIN SYKES, OF BUFFALO; NEW YORK.

MACHINE FOR CUTTING GEAR TEETH.

Application filed December 28, 1923. Serial No. 683,188.

This invention relates to improvements in machines for forming the teeth of gears, and

while the invention comprises certain fea-' tures which will be found advantageous in cutting straight toothed gears, such as spur wheelsand pinions for example, it is more particularly concerned with a machine for cutting of helical or double helical teeth upon a gear blank, in which one or more cutters H) are moved across the face of the gear blank during the cutting operation. The cutters are given, besides this reciprocatory movement across the face of the blank, a helical or twisting movement when cutting helical l5 teeth, a bodily relieving movement to enable them to clear the work during their inoperative strokes, .and to bothcutters and work is imparted a continuous generating feeding movement to present the entire surface of 120 the blank to the cutters.

The present application deals particularly with improvements in machines of the general t pe shown in my co-pending application, erial No. 641,126, filed May 24, 1923,

2:5 and is concerned with certain features of con struction designed to improve the operation ,7 of machines of this character, particularly when they are used to cut gear teeth upon relatively heavy blanks or blanks of large diameter. The invention also seeks to improve in certain respects the power transmitting means to the various parts of the machine and the controlling devices by which the transmission of power may be controlled.

To this end, I have shown controlling mechanism for the various parts of the machine, such that the control of the machine may be effected almost entirely from one point at the front thereof.

One object of my invention is the provision of improved means for imparting a relative approaching movement to the cutters and blank, so that the cutters may be properly fed up to the blank at the beginning of the cutting operation.

Another object of my invention is to provide a machine of this character in-which the blank is mounted in relatively fixed standards with reference to the bed of the machine, the cutters being mounted upon a movable carriage which may be moved to; ward the blank axis to provide for the engagement of the cutters with the blank and for the proper depth of tooth to be out.

A still further object of my invention is to provide for the operation of the machine at a plurality of different speeds relatively to the primary source of power. 1

A still further object of my invention is to provide for the imparting of the generating or feeding movement to the cutters and blank at a plurality of speeds relatively to the reciprocating and twisting movements of the cutters. e

A still further object of my invention is to provide means for setting up the cutters to the work which may be operated either manually, or from a suitable source of power, such as an electric motor.

A still further object of my invention is to provide a series of electrically controlled devices for the various operating parts of the machine, so that the operation of these parts may be controlled from a point adjacent the front of the machine'readily accessible to the operator.

Further, the invention is designedto simplify generally the operation of machines of this character. 2

To these and other ends the invention consists of the novel features and combination of parts to be hereinafter described and claimed.

In the accompanying drawings:

Fig. 1 is a partial plan view of a gear cutting machine embodying my improvements.

Fig. 2 isa continuation of the view shown in Fig. 1 showingthe rest of the machine.

Fig. 3 is a side elevational view of the parts of the machine shown in Fig. 1.

Fig. 4 is a side elevational view .of the parts of the machine shown in Fig. 2, the blank being omitted.

Fig. 5 is a front elevational view of the machine.

Fig. 6. is a rear elevational view of the machine.

. Fig. 7 is a partial side elevational view of the machine from the side opposite that shown in Fig. 3.

Fig. 8 is a diagrammatic view of theelectrical circuits of the control mechanism.

Fig. 9 is a sectional view on line 9.9 of Fig. 1.

Fig. 10 is a sectional view on line 10--10 of Fig. 3.

Fig. 11 is a sectional View on line 11-11 of Fig. 9.

Fig. 12 is a sectional View on line 12-12 of Fig. 1.

Fig. 13 is a sectional view on line 13-13 of Fig. 1.

. Fig. 14 is a sectional view online 1414 of Fig. 12.

Fig. 15 is a sectional vieWon line 1515 of Fig. 1. r

Fig. 16 is an enlarged detail front view of the solenoids and cooperating mechanism for actuating certain clutches.

Fig. 17 is a section on line 17-17 of Fig. 3. Referring more particularly to Figs. 1 and 3, the particular embodiment of my invention which I have selected to illustrate and describe comprises a main base consisting of 4 the bedplates and 11 with the guideways 12 and 13 thereon. At the front portion of the bedplate 10 is mounted a suitable standard 14 provided at. its upper end with journals 15 and 16, rotatably carrying a headstock 17 adapted to support one end of the shaft 18 upon which the gear blank 19 is mounted. The other end of the shaft 18 is mounted in a. suitable tailstock 20 supported by a standard 21 slidably mounted upon a base-plate 22 at the forward end of the bedplate 11. The standard 21 may be moved longitudinally of the shaft 18 to assist in placing the blank in the machine at the beginning of a cutting operation and remove it therefrom after the teeth have been cut in its periphery. The movement of the standard is accomplished by means of the handwheel 23.

The blank ma be lodged a ainst the ed es of L shaped arms 24, radial ab e upon a plate 25 mounted upon the headstock. Upon the right hand end of the blank carrying shaft 18, as shown in Fig. 2, is secured an indexing or wormwheel 26 provided with gear teeth at its periphery with which are adapted to enga e the teeth of a worm carried by the shaft 2 While the tailstock supportm one end of the blank carrying shaft is pre erably movable to facilitate the lacing of the blank in position in the mac ine, it may be noted that it is preferred to mount the blank carrying standards in fixed positions relatively to the longitudinal dimensions of the machine, so that there will be no bodily movement of the blank lengthwise of the bed lates 10 and 11. I

lfiaon the bedplates 10 and 11 is slidably mounted a main carriage 30 upon which a large part of the operating mechanism for erforming the cutting operation is carried. his main carriage is adapted to bemoved toward and from the gear blank, suchmotion, however, ordinarily taking place at the beginningand .end of the. operation of the machine upon a blank, as, when the g cutters have once been set 11 to the work so as to cut teeth of the required depth, the entire gear generating operation will usually proceed without any change in the posithreaded collar 34 acting 1y adjust tion of the main carriage. To this end I have rotatably mounted in journals 31 and 32 upon the bedplate 11 a threaded shaft 33. This shaft passes through and engages the threads of an internally threaded collar, or bushing, 34, rotatably mounted in a 'ournal 35 secured to the main carriage 30.

pon one end of this bushing is integrally formed a spiral gear 36, the teeth of which are engaged by a second spiral gear 37 mounted upon a shaft 38 rotatably mounted inzjournals 39, 40 and 41 secured to the carriage. Uponthe end of this shaft, opposite the gear 37, is a gear 42 meshing with .the gear 43 of a longitudinally disposed rotated and through it the shafts 44 and 38, spiral gear 36 and collar 34,-the turning of this collar on the threads of the rod 33 which is fixed against longitudinal movement in the journal 35, will cause the carriage 30 to move lon itudinally of the bedplates 10 and 11. fiuring this operation the rod 33 remains stationary, the internally as a. nut and being moved longitudinally of the bed. of the machine by engagement with the threads of .the rod.

In order to provide power operated means for moving the carriage along the bedplates 10 and 11, I have mounted at the rear of the machine a motor 50, upon the shaft 51 of which is mounted a worm 52 engaging the teeth of a worm wheel 53 secured'tothe rear end of the rod 33. The worm 52 and wormwheel 53 ma be enclosed in a suitable casing 54. hen the'mo'tor is set in operation the worm-wheel 53 is rotated, and with it theethreaded shaft 33. The threaded collar 34 is prevented from rotation at this time b the engagement of the spiral gear 36 wit the gear 37, the collar acting as a stationary nut, and the carriage is thus moved longitudinally of the bedplates by the rotation of the shaft 33. The

-motor 50 is arranged so that it may be reversed in direction to rotate thev rod 33 in the 0 )posite direction to withdraw the cutters from the work when such movement is desired.

At the front portion of the main carriage 30 is provided a guideway 55 in which is mounted a reciprocating slide 56, the

slide being held in position by means of upper and lower plates 57 and 58 which project over the edges thereof. This slide isv reciprocated by meansof a crank 59 secured upon theforward end of a shaft 60 and provided with a crank-pin 61 engaging with the slide.

In the preferred embodiment of my invention shown in the drawings I employ .cutters in the form of pinions or gears, as

stroke of each cutter ends in a plane at right I angles to the blank axis where the two halves of each tooth' join; a helical or twisting movement imparted to the cutters during their operative strokes for the cutting of helical teeth; a relief movement whereby each cutter is moved away from the workupon the return stroke so as to eflect a slight clearance between the cutter and the work during this stroke; andfourth, a continuous rotating movement at the same peripheral speed as that imparted to the blank, whereby the blank may be continuously fed to the cutters until the entire surface of the former has been operated upon.

To effect the reciprocating movements of the cutters they are secured to the main car-x riage slide 55 so that they travel with this slide 1n its movement transversely of the bed. Theright hand cutter 62, as shown in Fig. 11, is rigidly mounted upon a sleeve 63, the sleeve being rotatably carried within a journal 64 of acutter carriage 65. The left hand cutter is sir'nilarlykeyed to a hollow sleeve 67 rotatably mounted in 'a journal 68 of a second carriage 69. The cutter carriages 65 and 69 are movably mounted in guideways 70 in blocks 71, inwhich guideways the carriages have a limited movement between end abutments 72 and 7 3. The carriages are retained in place in these uideways between the abutments 72 and 3 by means of plates 74, which overlie the up er and lower edges of the carriage bases 5. The supporting blocks 71 are adjustably mounte in the main carriage slide 55 by means of threadedrods 77 and 77 suitably journaled in the main slide and engaging the threaded lugs 78, 79 and 80 upon the rear faces of the blocks 71. It will be noted.

that each of these rods is threadedly engaged with the lugs 78, 79 and 80 of only one of the carriage slide blocks 71, and as clearly shown in Fig. 11, passes loosely through the lugs of the other block so as to rotate freely therein. In this manner each rod is engaged with only one of the carriage slide blocks so that eachof the blocks may be adjusted across the slide in either direction independentl of the other. The blocks 71 are also hel in place in guideways in the slide 56 by means of plates 81 which overlie the edges of the blocks. It will be a parent that by rotating the rods 77 and 7 the cutter carriages, and therefore the cutters, may be independently adjusted along the main slide 56 to properly position each-cutter relatively to the slide, and to position the cutters relatively to each other, so that the distance between them may be varied. In this way, the cutters may be adjusted for different sized blanks, as it will be obvious that in order to operate satisfactorily the a distance greater than one-half the width of the peripheral face of the blank. In other words, when one cutter is at the middle'of the blank or at the extreme end of its cutting operation, the other cutter should clear the edge of the blank so that upon the return stroke a complete cut across the ad'acent half of the peripheral face of the blan will be effected.

It will also be apparent that when the shaft 60 is rotated by meansto be hereinafter described. ,the crank 59 will be rotated and the slide 56 will be reciprocated to move the cutters across the face of the blank, as

this slide controls the position of the cutters through the agency of the cutter carriages 65 and 69. with their journals 64. and 68.

At the same time that the cutters areyrecutters must not be set closer together than ciprocated across the face of the work they I are also given a twisting or helical motion if it is desired to cut helical teeth u on the blank. The preferred mechanism or imparting this motion to the cutters is now described. I

The sleeve 63 upon which the right hand cutter is mounted is' secured by means of a bolt 85 and clutch teeth 86 to the end of a spindle or shaft 87, this spindle passing through the sleeve 67 of the left hand cutter and havlng secured upon its left hand end a helical guide 88 by any suitable means. The

' guide 88 isslidably mountedwithin the 1101- low hub or sleeve 89 ofa worm-wheel 90,

and to this hub is secureda helical nut 91 which cooperates with the guide or sleeve 88;

Likewise, the sleeve 67 upon which the left hand cutter is ri 'dly mounted 1s rigldly secured to the rig t hand end of a second helical guide 92 slidabl mounted 1n the hollow hub 93 of a secon worm-wheel 94. A helical guiding nut 95 similar to the nut 91 is secured upon the inner surface of the hol and, 67 upon which the cutters are secured, will, due to the camming action. of the guiding nuts 91 and 95, impart to the cutters a twisting or helical motion as they are reciprocated across the face of the work. The cutters, will, of course, be twisted or moved along in one direction during the operative.

or cutting stroke of the cutters, and will be; moved in the opposite direction during an inoperative stroke so that the teeth of the. cutters will be properly backed out of the helical grooves which have been out.

It has been found desirable, particularly in cutting straight gears and in cutting gears in which the angle of the helix is relatively small, to provide a way to relieve each of the cutters at the end of each opera- I tive stroke so that when the cutter is being will not drag thereupon.

backed out of the work the cutting edge The means by which this is accomplished will now be described.

As has been previously described, the cut ter carriages 65 and 69 are mounted in guideways 70 in the blocks 71. As shown in Fig. 11, these guideways are inclined relatively to the axis of the cutters, and as the carriages have a limited movement longitudinally of the guideways between the abut; ments72 and73, it will be apparent that the carriages, and thus the cutters, may be moved toward and away from the work to a limited extent. As shown in Fig. 11, the

left hand cutter is practically at the end of its operative stroke and is about to begin its return stroke. The cutter has been carried to this position by contact of the cutter carriage 69 with the abutments 73. When, however, the main slide begins its return stroke, the blocks 71 will have a limited movement independently of theacutter carriage 69 until the abutment 72 is moved against the base of the cutter carriage. During this relative movement the cutter carriage will be permitted to move slightly in the guideway 7 O, and as this guideway is inclined, will be slightly withdrawn from the work.

The right hand cutter 62 is about to begin an operative stroke and hence the cutter carriage is shown in the position where it is in contact with the abutment 73 of the corresponding block 71. The cutters are normally urged into contact with the abutments 73 by means of springs 97 which react against the abutments 72 and against the carriages. As the cutters are normally urged against the abutments 73 toward the blank upon which they are operating, it has been found desirable to provide some means for forcing the carriages against the abutments 72 against the tension of the springs when each carriage comes to the end of its cutting stroke.

For this purpose I have mounted, in a bearing 100 upon a main frame and in bearings 101 and 102 upon the plates 74, ashaft 103. To this shaft are keyed a pair of camming fingers 104 and 105 adjacent the journals 101 and 102, the cammingfingers being attached to these journals so that they are moved longitudinally of the shaft 103 as the cutter carriages and cutters are reciprocated, butv are also permitted an oscillating movement with the shaft 103. As shown more particularly in Fig. 11, the camming finger 104 is provided with a camming edge 106 coacting with a complemental cam lug 107 formed integrally with the carriage 69 to urge this carriage against the abutment 72 against the action of the spring 97 when the shaft 103 is oscillated. It will also be understood that when the shaft is returned to its original position, the carriage 69 will again be moved against the abutment 73 by the spring. Likewise, the cammin finger 102 is provided with a camming sur ace 108 which coacts with a cam-lug 109 on the carriage to force this carriage away from the work against the action of its spring 97. As shown in Fig. 11, the left hand outter has been .forced to a position in which it is relieved from the work by the action of the cooperating cam finger 104.

It will be apparent that when the cutters are moved toward andaway from the work in order that they may be relieved upon their inoperative movement, rovision must be made to permit correspon ing movement of'the shaft upon which these cutters are mounted. The shaft 87 of the right hand cutter which passes through the sleeve 67 is provided with sufficient clearance within this sleeve to permit the slight bodily movement which is necessary and similar movement-is also permitted within the collar 96. The helical guides 88 and 92 are, however, closely fitted within the hubs 89 and 93 of the worm-wheels 90 and 94, and it is, therefore, necessary to provide for a bodily movement of these wheels. For this urpose the wheels are mounted within casings 110. and 111, shown more particularly in Fig. 9, which casings are provided at their upper and lower portions with guiding tongues 112 and 113 slidably mounted in guideways 114 and 115 in upper and lower supports 116 and 117 upon the main carriage. In front of the casings 110 and 111, as shown in Fig. 5, is mounted a rock-shaft 119 rovided with suitable cams 120 and 121-wh1ch act against the faces of the casings to move the latter rearwardly at the instant that the cutters are moved away from the work at the beginning of the return stroke.

lim

A link 122 connects the rock-arm 123 upon the shaft 119 to a rock-arm 124 upon a shaft at the rear side of the main carriage and bifurcated at its lower end, as at 132, to engage with opposite faces of a cam disk 133 secured to the rear end of the shaft 60. Any suitable means, 'such for instance as is shown in my co-pending application No. 641,126,

. may be provided to return the worm-wheel casings to their original position after their release by the cams 120. i

To impart a continuous, rotating, generating movementto the cutters, vertically disposed shafts 134 and 135 are mounted at the front of the worm-wheel casings 110 and 111, and upon the shafts are mounted worms (not shown) to engage with the teeth of the worm-wheels 90 and 94. At the upper end of these shafts are provided gears 136 and 137 with which meshes a gear 138 secured to a shaft 139 rotatably mounted in suitable bearings on the maincarriage. At its lower end this shaft is provided witha bevel gear 140 driven froma similar gear 141 upon alongitudinally disposed shaft 142 mounted upon the bedplate 11. As the carriage, as has already been described, moves along the bedplate, it will be necessary to mount the gear 141 so that it is slidable along its shaft,

in order that power will be transmitted to the shaft 138 regardless of the position of the carri. e.

It is, 0 course, necessary that the blank be rotated at the same peri heral speed as the cutters, and to this en a gear 143 is mounted upon the shaft 142, as shown in Fig.

' 1, and is engaged by a gear 144 upon a shaft 145. The shaft 145 in turn drives a shaft 146 connected through reducing gear- .ing, designated generally by the numeral 147 to assha'ft 148, which in turn drives the shaft "149. A gear 150 on the end of this shaft engages a gear 151 uponthe shaft 152 provided at its-forward end with a gear 153 in engagment with the gear on the lower end of the worm-shaft 27, which, as has already been described, drives the indexing wheel 26 securedto the shaft of the gear blank. It will be apparent that whenever a rotating motion 1s imparted to the cutters, a similar motion will be imparted to the blank, and as both cutter and blank are driven b the same shaft 142 it will be apparent t at they will be rotated at certain relative speeds. This speed may be changed for blanks of different sizes by the use of different reducing gearing 147, and for this purpose this gearing is mounted upon a studshaft 160 adjustable in a slotted arm 161, mounted to swing about the shaft 148.

In order that the blank and cutters may be rotated in a reverse direction which will sometimes .be found desirable, I have mounted on the bedplate 10 a motor 165 having upon its shaft a gear 166 engaging with a gear 167 loosely mounted u on the shaft shown in Fig. 6. From the pump a pipe 17 3 leads to a position to deliver a lubricant to the blank and cutters. A

Upon the shaft 60 is mounted a gear 175 constantly in mesh with a gear 176, shown more particularly in Fig. 10, slidably mounted upon the main driving shaft 177. This driving shaft is rotatably mounted upon the main bedof the machine, and for this reason it is necessary to have a: sliding connection between it and the gear 176. The shaft 177 at its rear end passes through and is journaled in a transmission housing 178 in which is mounted a suitable change speed gearing, which will now be described. Journaled in this housing are two additional shafts, a counter-shaft 179 and a driving 7 shaft 180 which extends from the housing and is driven by a suitable motor 181 the shaft of which is connected to the shaft 180 by a magnetic clutch 182.. To the shaft 180 are secured a plurality of gears, four in numdriving shaft. The gears on the countershaft are mounted in pairs, and between them are clutch collars 191 and 192 slidably keyed to the shaft whereby any of the gears may be selectively clutched to this shaft, sothat it may be driven from the driving shaft. As the gears on the driving shaft, andv consequently the gears on the countershaft which mesh therewith, are of different diameters, thecounter-shaft may be driven at four different s eeds from the driving shaft. Besides the our gears just described, which are loosely mounted uponthe countershaft 17 9,two gears 195 and 196 are secured thereon, and are constantly in mesh respectively with gears 197 and 198 loosel Stantly in mesh with one. of the gears on the collar 199 is mounted between these gears and may be shifted by means of a lever 200 to clutch either of these gears to the shaft 177. It will be apparent that the shaft 177 may be driven at two different speeds relativel to the shaft 179, and, therefore,-at eight di ferent speeds relatively to the shaft 180. It will also be noted that in my transmission mechanism I may make use of double helical 10 gears which are advantageous for this kind twisting movement to the cutters, and also furnishes the power through the cam disk 133 for imparting the relief -movement to the cutters. The rotating movement imparted to the cutters and blank is effected v through the shaft 142 which is driven from the shaft 177 by mechanism which I will nowdescribe.

The shaft 177 extends from the transmission housing 178 at the rear end thereof and 0 mounted upon this shaft, in a suitable housing 205, are two gears 206 and 207. These gears are constantly in mesh with gears 208 and 209, the former of which is loosely mounted upon a shaft 210, and the latter 86 loosely mounted u on a sliding sleeve 211 keyed to this sha t. To the inner end of this sleeve is secured a clutch, plate 212 disposed between the gears 208 and'209, and adapted to engage complemental clutch ele-' 40 ments with which the gears are provided to clutch either of these gears selectively to the shaft 210. On the end of the shaft 210 is secured a spur gear 213 which meshes with a gear'214 on the end of the shaft 142, so that 46 the latter is driven upon the rotation of the shaft 210. It will be understood that by this means the shaft 142 may be driven at two different speeds relatively to the shaft 17 7, and thus the rotating feeding movement 30 of the blank and cutters may be varied relatively to i the reciprocating and twisting movement of the CUttGIS WhICh is sometimes desirablein the operation of the machine.

Upon the'sleeve 211 is mounted a collar 215 engaged by a clutch shifting yoke 216 secured to a horizontally disposed rock-shaft 217 carried in suitable bearings on the housing 205, so that upon the oscillation of this shaft the shifting yoke will move the sleeve 211 longitudinally of the shaft 210 to which it is. keyed. To move the clutch-plate 212 into engagement with one'or the other of the gears 208-and 209, or to an intermediate neutral osition, a rock-arm 218 is connected to the shaft-217 and is in turn connected by a link 219 to a. second rock-arm 220 secured at the end of a longitudinally disposed shaft 221 which passes through thetransmission housing, and as shown in Fig. 16, projects from the end of this housing adjacent to the operating members 222 and 223 of solenoids 224 and 225. To the members 222 and 223 are secured fingers 226 and 227 designed to engage the teeth 228 and 229 of a disk 230 secured to the shaft 221. The solenoids may be operatively mounted upon a bracket 231 secured to the transmission housing.

As shown, the clutch-plate 212 is in its neutral position and the fingers 226 and 227 are shown in position to engage respectively the lower ones of the teeth 228 and 229. If, when the parts are in this sition, the solenoid 224 is operated, the nger 226 engaging below the lower tooth 228 will rotate the disk one step in a clockwise direction, and will serve to move the clutch-plate 212 into engagement with the gear 208 and connect the gear to the shaft 210. If at this time-the solenoid 225 is energized, the finger 227 will engage below the upper tooth 229 and move the clutch disk 212 to the right, as shown in Fig. 14, to its neutral position out of engagement with the gear 208. If the solenoid 225 is energized a second time, the disk 230 will be moved a second step in an anti-clockwise direction and will shift the clutch-plate so as to connect the gear 209 to the shaft 210.

I have found it convenient and desirable to locate the controlling switches of the electrically operated mechanism at'the upper part of the front side of the carriage, as shown at 240 in Fig. 3. As this carriage is movable with respect to the base 11 upon which the circuit wires which lead to the various mechanisms are supported, I have arranged a sliding contact device by means of which the circuits may at all times be completed by the switches, regardless of the position of the main carriage. .These wires,

designated generally by the numeral 241, are bare of insulation adjacent the bed, as shown in Fig. 3, and at their forward ends are connected to insulated wires carried in the cable 242. As shown more especially in Fig. 17, a trolley-arm 243 is secured to the movable carriage and carries a plurality of insulated shoes 244 in contact with the bare wires 241. From these shoes the wires lead through the cable 245 to the switches 240, so that the cur rent may be completed through the switches. The bare wires 241 may be protected by a guard plate 246 secured to the base 11.

In Fig. 8 I have shown dia rammatically the connections through Wl'liC l'l the various circuits are completed by the switches'on the movable carriage. The switch 240" is a double throw switch designed to be thrown in either direction from its neutral position, shown in the drawings, into contact with the terminals 250. and 251 to energize the relays to energize the relays 258 and 259 respec- 252 and 253 which in turn complete the circuits through the solenoids 224 and 225 recircuit through the magnetic. clutch 182 which connects the prime motor 181 with the shaft 180. It will be understood that this motor is normally continuously in operation,

and may be controlled in the usual or any desired manner, which I have not deemed necessary to illustrate.

The switch 240 may be placed/in engagement with either of the contacts 256 or 257 tively, which relays in turn energize the relays 260 and 261. The relay 260 completes the circuit throu h the motor 50 to operate the threaded shaft 33 to set up the cutters to the work. The relay 261 also serves to complete the circuit, butcauses the current to pass through the motor in an opposite direction so as to reverse the motor and back the cutters away from the work.- The motor 165 which serves to rotate the blank and cutters in a reverse direction to that given themby the shaft 142, may be operated by any desired means.

The operation of my. machine may be briefly described as follows:

1gear blank mounted in position With a upon the s aft 18, as shown in Fig. 2, the motor 50 may be set into operation by the switch 240 to rotate the shaft 33 in a direction to feed the cutters up to the work by moving the main carriage 30 on the uideways 12 and 13. It will be. understoo that this motor is designed to move the carriage at a considerably greater speed than is effected by the hand wheel 45, and it is, therefore, desirable to use the motor for coarse adjustments of the carriage into a position wherein the cutters are closely adjacent to the work; It will also be understood that the driving motor 181 and the reversing motor 165 are in constant operation during the operation ofthe machine, both of these mo' Qated to actuate the magnetic clutch 182 and set the machine in operation. The des red speed of the'cutting tools may be obtained through the change speed mechanism in the housing 178, whereby the cutters may be driven at eight. different speeds relatively to that of the motor.' Likewise, the desired .speed of the feeding generating movement of the cutters and blank is obtained by shifting the clutch yoke 216 by means of the solenoids 224 or 225 to engage the gear 208 or the gear 209 with the shaft 210. The speed of the operating mechanismof the machine, as well as that of the feed are governed by a number of factors, including the hardness of the material of the blank, the kind of material used in the cutter, the form and condition of the cutter, the rigidity of the gear blank and the pitch of the gear to be cut. With the mechanism in operation, the hand wheel 45 is turned to feed the cutters toward the blank. A very fine adjustment can be obtained by means of the rotation of this hand wheelso that the proper depthof the tooth to be out can be accurately gauged. When the carriage has been moved up to the proper position so that the cutters cut to depth in the gear blank, the feeding move ment by the hand wheel 45 is stopped. The

continued operatfon of the machine, due to the continuous generating or feeding rotary movement imparted to both the cutters and blank at the same peripheral velocities, causes the blank to be fed to the cutters until its entire periphery has been subjected to their action and teeth have been cut over the entire periphery of theblank. If, during the cutting of a gear, it is desired to cause the cutters, to traverse the work a second time, the cutting mechanism may, of course, be operated at a higher speed during the second cut, and likewise, the rotating feeding movement of the cutters and blank could be effected at a higher speed. These higher speeds are obtained respectively through the change speed mechanism contained in the housing 178, and by means of the sh fting of the clutch plate 212., If, for instance, the gear 209 is in engagement with the shaft 210, and it is desired to change the speed of the rotative feeding movement of the cutters and blank, the switch 240 may be moved into contact with the terminal 251. The solenoid 224 is thereby energized and the ,clutch plate 212 is moved out of engagement with the gear 209 into a neutral position. If the switch 240 is moved to this neutral position and again moved into contact with the terminal 251, the solenoid 224 will be again energized and the clutch plate moved to clutch the gear 208 to the shaft 210 so that the speed of the shaft 142 will be changed relatively to that of the shaft 177.

To back the cutters away from the work, the switch 240 may be operated to reverse the motor 50 so that the shaft 33 will be turned in a reverse direct on and move the main carriage 30 rearwardly along the guideways 12 and 13.

If, for anyreasomit is desired to reverse the rotating feeding movements of the blank and cutters, the motor 165 may be clutched to the shaft 149 by means of the shifting lever 169, and the cutters and blanks will be rotated in a reverse direction from that inipartedto them by the gears 208 or 209. It

will be understood that during this operation the clutch plate 212 is in its neutral position.

I do not claim herein the particular method of and means for moving the cutters across the face of the gear and relieving them therefrom upon the return stroke, or other features described and claimed in my rior applications Nos. 641,125 and 641,126, led May 24, 1923, nor do I claim per se herein the features of the change speed mechanism shown particularly in Fig. 10 of the drawings, which are described and claimed inmy application No. 699,499, filed March 15, 1924.

While I have shown and described a preferred embodiment of my invention, it will .be understood that it is not to be limited to all the details shown, but is capable of mod ification and variation within the spirit of the invention and the scope of the appended claims.

What I claim is:

1. A gear cutting machine comprising a bed, means for supporting a gear blank upon a fixed axis on said bed, a carriage mounted on said bed for movement towards and away from the blank, a cutter mountedon said carriage and adapted to be moved with said carriage to and from cutting engagement with the blank, operating means for giving said cutter a translatory movement across the face of said blank, means for moving said carriage towards said blank until the depth of the cut produced by the action of said cutter on said blank reaches a predetermined limit, said blank being stationary during the movement of said carriage, and means for rotating said blank thereafter to cut a series of teeth on the periphery thereof while maintaining a fixed relationship between the blank axis and the (iarriage.

2. A gear cutting machine comprising a bed, means for supporting a gear blank upon a fixed axis on said bed, a carriage mounted on said bed for movement towards and away from the blank, a cutter mounted on said carriage and adapted to be moved with said carriage to and from cutting engagement with the blank, operating means for giving said cutter a translatory movement across the face of the blank, means for moving said carriage towards said blank until the depth of the cut produced inthe blank by the action of the cutter thereon reaches a predetermined limit, said blank being stationary during the movement of said carriage, and means for giving the blank a con-- tinuous rotary movement thereafter to cut a series of'teeth thereon, the axis of the blank being maintained in fixed relationship to the carriage during such rotation.

. 3. A gear cutting machine comprising a bed, means for supportinga gear blank upon a fixed axis on said bed, a carriage mounted on said bed for movement towards and away from the blank, a cutter mounted on said carriage and adapted to be moved with said carriage to and from cutting engagement with the blank, operating means for giving said cutter a translatory movement across the face of the blank, means for moving said carriage towards said blank until the depth of the cut produced in the blank by the action of the cutter thereon reaches a predetermined limit, and means for rotating the blank through an arc of substantially 360 thereafter, while'maintaining a fixed relationship between the blank axis and the carriage.

4. A gear cutting machine comprising a .bed, means for en orting a gear blank upon a fixed axis on said bed, a carriage mounted on said bed for movement towards and away from the blank, a cutter mounted on said carriage and adapted to be moved with said carriage-to and from cutting engagement with the blank, operating means for giving said cutter a translatory movement across the face of said blank, means for relieving the cutter from the blank during a part of the translatory movement, means for moving said carriage towards said blank until the depth of the cut produced by the action of said cutter on said blank reaches a predetermined limit, the blank being stationary during the movement of said carriage, and

means for rotating the blank after the out has reached a predetermined limit while maintaining a fixed relationship between the blank axis and the carriage. Y

5. A gear cutting machine comprising a bed, means for supporting a gear blank upon a fixed axis on said bed, a carriager mounted on said bed for movement towards and away fromthe blank, a cutter mounted on said carriage and adapted to be moved with said carriage to and from cutting engagement with the blank, operating means for giving said cutter a translatory movement across the face of the blank, means for relieving the cutter from the blank during a art of the translatory movement, means ormoving said carriage towards said blank until the depth of the cutproduced in the blank by the action of the cutter thereon reaches a predetermined limit, said blank being stationary during the movement of said carriage, and means for giving the blank a continuous rotary movement thereafter to cut a series of teeth thereon, the axis of the blank being maintained in fixed relationship to the carriage during the rotation of the blank.

b 6, A gear cutting machine comprisinga bed, means for supporting a gear blank upon a fixed axis on said bed, a carriage mounted on said bed for movement towards and away from the blank, a cutter mounted on said carriage and adapted to be moved with said carriage to and from cutting enga ement with the blank, operating means I or giving said cutter a translatory movement across the face of the blank, means for relieving the cutter from the blank during a part of the translatory movement, means for movingv said carriage towards said blank until the depth of the cut produced in the blank by the action of the cutter thereon reaches a predetermined limit, and means for rotating the blank through an arc of substantially 360 thereafter, while maintaining a fixed relationship between the blank axis and the carriage.

7. A gear cutting machine comprising a bed,means for supporting a gear blank upon a fixed axis on said bed, a carriage mounted on said bed for movement towards and away from the blank, a cutter mounted on said carriage and adapted to be moved with said carriage to and from cutting engagement with the blank, operating means for giving said cutter a translatory movement across the face of the-blank, means for giving said cutter a rotary movement during such trans latory movement, means .for moving said carriage towards said blank until the depth of the cutproduced by the action of said cutter on said blank reaches a predetermined limit, the blank being stationary during the movement of said carriage, and means for rotating the blank and the cutter after the out has reached a predetermined limit while .maintaining a fixed relationship between the blank axis and the carriage.

8. A gear cutting machine comprising a bed, means for supporting a gear blank upon a fixed axis on said bed, a carriage mounted on said bed for movement towards and away from the blank, a cutter mounted on said carriage and adapted to be moved with said carriage to and from cutting engagement with the blank, operating means for giving said cutter a translatory movement across the fa e of the blank, means for giving said cutter :Nptary movement during such translatory movement, means for moving said carriage towards said blank until the depth of the cut produced in the blank by the action of'the cutter thereon reaches. a predetermined limit, said blank being stationary during the movement of said carriage, and means for continuously rotating said cutter and blank after the out has reached a predetermined limit, the axis of the blank being maintained in fixed relationship to the-carriage during said rotation.

9. A gear cutting machine comprising a bed. means for supporting a gear blank upon a fixed axis on said bed, a carriage mounted on said bed formovement towards and away from the blank, a cutter mounted on said carriage and'adapted to be moved with said carriage to and froi'n cutting engagement with the blank, operating means for giving said cutter a translatory movement across the face of the blank, means forgiving said cutter a rotary movement during such translatory movement, means for moving said carriage towards said blank until the depth of the cut produced in the blank by the action of the cutter thereon reaches a prede- 7 termined limit, and means for rotating the blank through an arc of substantially 360, while maintaining a fixed relationship between the blank axis and the carriage.

10. A gear cutting machine comprising a 7 bed having a horizontally disposed guideway thereon, means to mount a gear blank upon a fixed axis on the bed, a carriage slidably mounted on the bed for movement toward and from the blank axis, cutter spindles rotatably mounted on the carriage, cutters mounted on said spindles, operating mechanism for the cutters mounted on the carriage, and said cutter spindles being mounted on said carriage for movement relatively thereto in a direction transverse to their axes to relieve the cutters from the blank,

11. A gear cutting machine comprising a bed having a horizontally disposed guideway thereon, means to mount a gear blank upon a fixed axis on the bed, a carriage slidably. mounted on the bed for movement toward and. from the blank axis, cutter spindles rotatably mounted on the carriage, cutters mounted on said spindles, operating mechanism for the cutters mounted on the carriage, and said cutter spindles belng mounted on said carriage for movement relatively thereto in a direction transverse to their axes to relieve the cutters from the blank, and means to efiect independent relief movement of the cutter spindles at predetermined times in their operation,

12. In a gear cutting machine, a bed, a gear blank operatively mounted thereon,

a carriage slidably mounted on the bed, cutters and cutter operating mechanism mounted on said carriage, said cutter operating mechanism including means to cause 11 said cutters to traverse the face of the work in a reciprooatory movement, and means to rotate the cutters on their axes, a source of power, a shaft mounted on the bed and connected to said reciprocating mechanism, a second shaft mounted on the bed and connected to said cutter rotating mech-, anism, said connections being slidable whereby the cutter mechanism may be driven from said shafts regardless of the positibn of the carriage, and means for rotating said shafts.

13. In a gear cutting machine, a bed, a gear blank operatively mounted thereon, a carriage slidably mounted on the bed, cutters and cutter operating mechanism mounted on said carriage, said cutteroperating mechanism including means to cause said cutters to traverse the face of the work in a reciprocatory movement, in an axial direction, and means to rotate the cutters on, their 1.50

axes, a source of ower, a pair of shafts mounted on the bed and means for operating said cutter operating mechanism from said shafts, including gears slidably mounted on said shafts and connected to said operating mech'anismf 14. In a gear cutting machine, a bed, means for operatively mounting a blank thereon, a carriage movably mounted n said bed, cutters and cutter operating mechanism mounted on said carriage, meansfor moving said carriage toward and away from the blank to feed the cutters to the work, and both manually'and power operated means to. actuate said moving means in either direction. a

15. In a gear cutting machine, a bed,

means for operatively mounting a blank thereon, a carriage movably mounted on.

said bed, cutters and cutter operating mechamsm mounted on sa1d carriage, means for movlng said carriage toward and away from the blank to feed the cutters to the work, said means including both fast and slow acting means for coarse and fine adjustments.

16. In a gear cutting machine, abed, means for operatively mounting a blank thereon, a carriage movably mounted on said bed, cutters and cutter operating mechanism mounted on said ca'rria e, means for moving a said carriagetoward t e blank to feed the cutters to the work, said means including a threaded shaft rotatably mounted on the bed, a sleeve rotatably mounted on the carriage and provided with threads engaging those of the shaft, and means to rotate sai shaft while said sleeve is held stationary.

17 In a gear cutting machine, a bed, means for operatively mounting a gear blank thereon, a carriage movably mounted on said bed, cutters and cutter operating mechanism mounted on said carriage, means for moving said carriage toward the'blank to feed the cutters to the work, said means including, a threaded shaft rotatably mounted on the bed, a sleeve rotatably, mounted on the carriage and provided with threads engaging those of the shaft, and means to rotate said sleeve while said shaft is held in a stationary position.

'18. In a gear cutting machine, a bed, means for operatively mounting a gear blank thereon, a carriage movably mounted on said bed, cutters and cutter operating mechanism mounted on saidcarriage, means for moving said carriage toward the blank to feed the cutters to the work, saidmeans including a threaded shaft rotatably mounted on the bed, a sleeve rotatably mounted on the carriage'and rovided with threads engagin those of t e shaft, and means to rotate eit er said shaft or sleeve while the other of said elements is held in a stationary position.

19. In a gear cutting machine, a frame,

means for mounting a gear blank on said frame, a carriage movably mounted on the frame, cutting mechanism operatively supported on the carriage, means for moving said carriage toward and away from the blank to feed and withdraw the cutters from the work, including a threaded shaft, a motor to drive said shaft, and means. for reversing the direction of the motor.

I 21. In a gear cutting machine, a frame, means for mounting a gear blank on the frame, a carriage slidably mounted on the frame, a cutting mechanism mounted on said carriage, means to move said carriage toward and from the gear blank to feed the cutters to the work and withdraw them therefrom,

and both manually and power operated means to operate said moving means to move the carriage in either direction.

22. In a gear cutting machine, a frame, means for mounting a gear blank on the frame, a carriage slidably mounted on theframe, a cutting mechanism mounted on said carriage, means to move said carriage toward and from the gear blank to feed the cutters to the work and withdraw them therefrom, and both manually and power operated means to. operate said moving means to move the carriage in either direct1on, said power operated means comprising a reversing motor mounted on the frame and adapted to be driven in either direction.

23. In a gear cutting, machine, a bed,

means for operatively mounting a gearblauk on the bed, cutting mechanism comprising cutters mounted to move across the face of the gear blank to cut gear teeth therein, means-t0 impart a continuous generating rotary movement to the cutters and blank, a power source and a change spec mechanism whereby said cutting mechanism and blank may be driven fromthe power source at a plurality of speeds.

24. In a gear cutting machine, a bed, means,

for operativelymounting a gear -.blank 011 thebed, cutting mechanism-including cutters mounted to move across the face of the gear blank and to rotate in conjunction with the blank, driving, mechanism to impart said movements to the cutters, a motor, a change speed mechanism interposed between said motor and driving mechanism whereby the latter may be operated from the motor at a plurality of different speeds.

25,111 a. g ar cutting machine, a bed, 

